Needle-actuating cam for knitting machines



De@o 23 1924.

W. S. PARKER NEEDLE ACTUATING CAM Fon KNITTIEG MACHINES Filed Aug. 7, 1922 NP m @al Nw); EM MW XW E E E@ Q@ j" NEEMW NN .NM1 (N. MMJ\\\MV AM Q WWE NWN. MNM..

Patented ee. 23, i924.

J l rezan orrlcs.

WILLIAM S. PARKER, OF ROCKFOBD, ILLINOIS, ASSIGNOR T BURSON KNITTING COM- 'PANY, 0F ROCKFORD, ILLINOIS, A CORPORATION 0F ILLINOIS.

v NEEDLE-CTUTING CAM FOR KNITTING MACHINES.

Application led August 7, 1922. `Serial Nol/679,986.

To all whom. #may concern:

Be it known that I,

Rockford,'in the county of Winnebago and State of Illinois, have invented certain new and useful Improvements in Needle-Actuating Cams for Knitting Machines, of which the following is a speci cation. l

This invention pertaining in general to lo knitting machines, has more particular reference to the cams for advancing and retracting the needles, especially in straight knitting machines. .ln these, a cam slide for each bed of needles advances and retracts the needles upon each stroke and on certain strokes the needles will be held in an idle, retracted position, the cams acting on jacks which in turn operate the needles. rlension is imposed on the needles by suitable springs 2o for holding them against their seats and preventing displacement from the loop, especially when in the retracted position. It is desired that this spring tension shall -be as light as practicable, but with the cam slides as heretofore constructed, itl has been impossible to employ the desired lightness in degree of tension without imparing the knitting action. lln'other words, when the needles are under too light tension, there is a tendency (due to the cam construction) for them to advance during the idle stroke and` ski stitches.

t is the object vof the present invention, therefore, to provide means forl preventing strokes, thereby enabling the use of lighter tension on the needles and preventing the skipping of stitches.

Another object is do provide an improved cam struct-ure for advancing and retracting ,the needles, my invention relating more particularly to theA provision of supplemental cams adapted to be automatically moved into and out of operative position in which 'to prevent the advancement of the needles at a particular stage as will be explained more fully hereinafter.

Referring to the drawings,-

Figure 1 is a fragmentary perspective view of a needle-actuating 'cam slideA embodying my invention;

Fig. 2 is a fragmentary vertical section vthrough one of the needle beds of a straight lmitting machine showing the location of said cam slide;

WILLIAM S. Penman a citizen of the United States, residmg at f advancement of the needles during the idle Fig. 3 is a face view of the underside of the cam slide; v

Fig. 4, is a longitudinal sectional view through the cam slide taken substantially on the linee-4 of Fig. 3; and

Fig. 5 is a cross sectional view through the cam slide taken on the line 5 5 of Fig.

3, showing a cam slide in operativo relation to a needle jack.

The application of my invention will be better understood by reference to Fig. 2. which shows in brief a section throughv one of the needle beds of a straight knitting machine. It will be observed that the needle 8 urged against the bed plate 9 by a spring 11 is adapted to be retracted and advanced by means of a jack 12, Which Ain turn has 'an upstanding` lug 13 adapted to be operated by cams on a bar 141, slidnble in suitable ways on the machine frame.

The cam bar carries on its underside an advancing cam l5 and double retracting cams 16 and 17, these reference numerals being generally applied. The cam 15 -is fixed to a. sup-porting part 18 extending through an opening in the slide bar 14. which part in turn is fixed to a bar 19 disposed above said slide bar and pivotally attached thereto at 21. By means of an eccentric 22 operable between the bars 14 and 19, the cam 15 may be lowered into operative position as shown in Fig. 4J, in the plane of the jack lugs 13 in which veither of the cam faces 23 (depending on the direction of travel) will engage the lugs 13 and advance the jacks, and likewise the needles; and by partial rotation of said eccentric, the cam 15 may be raised to an inoperative position above the lugs 13 lso as not to advance the needles. The purpose oflowering and elevating the cam 15 is to throw the needles intoI and out of action as desired when knitting a tubular fabric, as is well` known in this art. y

The retracting cams 16 and 17 are fixcdly but adjustably attached to the bar 14.` these cams having faces 24, which by action of the jack lugs 13 are adapted to retract'the llt) as each jack a' shoulder27 which bears against the upper surface 28 of the cams 16 and 17 for limiting the retracting movement of the jacks, such surfaces are cut away at 29 to compensate for the surfaces 25 at the heel end of said cams. :These cams are in the present instance, respectively fixed to supporting parts 31 which are slidably guided on the guide 14 by guide plates 32 and adapted to be adjusted 1n the planes of the cam surfaces 24 which vary the distance to which the needles will be retracted, it being well known in this art that the further the needle is drawn down, the longer the loop, and consequently the looser the fabric. Suitable means, not shown, is provided for rigidly securing the cam-supporting parts 31 in any adjusted position. rlhe parts thus tar described have been used prior to my -invention.

lt is found, however, that when a com-v paratively light spring tension is imposed on the needles, there is a tendency for the needles to be advanced durin the idle stroke that is when the advancing cam 15 is raise partly by reason of the increased tension imposed by the first or leading' cam extension 25 which engages the jack lugs and' by the sudden release of such tension, causing the jack plug to spring forward in the cam-way33, assuming that the cam slide is traveling to the right, Fig. 3. lThis condition l have overcome by the provision of supplemental cam blocks 34 shaped to tit the cam-ways 33 and having a rear surface 35 in the plane of the heel surface 26. These supplemental cam blocks are adapted to be moved into and out of cam-Ways 33, preferably through suitable openings 36 in extensions 37 of the cam-supporting parts 31. ln the present instance, the supplemental cam blocks 34 have upwardly projecting ends 33 passing through the bar 14 and connected by means of evers 39, with the. cam-supporting part 18. As shown in Figs. 1 and 4, the levers 39 pivoted intermediate their ends at 41,'to the bar 14 are pivotally connected at their outer ends with the extensions 38 of the-supplemental cam blocks, and at their inner ends with the cam-supporting part 18. As a result of this construction, said cam blocks 34 will be lowered and raised to bring, their cam surfaces 35 into and out of operative position in the camways 33 by raising and lowering of the advancing cams 15. In other words, when said advancmg cam is in the loweredoperative position shownlin Fig. 4 (which is inverted), the supplemental cam blocks 34 will be elevated to an inoperative position, and upon elevating the advancing cam 15 to an inoperative position the cam blocks 34vwill thereby be lowered to their operative position, as shown' in Fig.' l (which islikewise inverted). With the supplemental cam venting the needles from being advanced during the idle stroke, thereby eliminating the dropping of stitches,`as explained above.

lt Jfollows that this construction enables the use of lighter spring pressure onthe needles, and is a factor 4in promoting longevity of the machine and accuracy in knitting.

:it is believed that the foregoing conveys a clear understanding of the objects prefaced v above, and while I have illustrated but a single working embodiment, it should be un-l Y derstood that considerable change might be lmade in the construction without departing from the spirit and scope of the invention as expressed in ,the appended claims:

' 'l claim:

1. 1n a straight knitting machine, the combination with a cam slide having cams for advancing and retracting the needles, the advancing cam being movable into and out of operative position, of a cam supplemental to one of the retracting cams` for preventing advancement yof the needles from their retracted position, and means formoving said supplemental'cam to inoperative position upon movement' of the advancing cam to operative position.

2. ln a straight knitting machine, the combination with the needle-actuatingcam slide which carries spaced retracting cams and an interposed advancing cam, theI latter adapted to be lowered and raised to and from the operative position in which a camway is defined between the cams for the passage of the jack lugs, of supplemental cam blocks movable into and out of said cam ways at the heel end of the retracting cams,

and means for automatically moving said supplemental cam blocks into and out of said cam-ways. i

3. In a knitting machine, a needle-actuating cam slide for advancing and retracting cams, the advancing cam being movable into andv out of operative position and each retracting cam having an extension at its. heel end for setting the stitch, and supplemental cams adapted to form continuatlons of the heel ends of said retracti'ngcams.

4. In a knitting machine, a needle-actuating cam slide for advancing and retracting cams, the advancing cam being movable into and out of operative position. and each retracting cam having an extension at its heel end for setting the stitch, supplemental cams adapted to form continuations of the heel ends of said retreating cams, and means operated by said advancing cam for moving said supplemental cams into and out of operative position. Y

5. In a knitting machine, a needle-actuating cam slide for advancing and retracting cams, the advancing cam being movable into and out of operative position and each Ietracting cam having an extension at its heel end for setting the stitch, supplemental cams 10 adapted to form continuations of the heel ends of said retracting cams, and means for operative, and vice versa.

. WILLMM s. PARKER. 

